diff options
Diffstat (limited to 'mm/khugepaged.c')
| -rw-r--r-- | mm/khugepaged.c | 64 |
1 files changed, 45 insertions, 19 deletions
diff --git a/mm/khugepaged.c b/mm/khugepaged.c index 728d7790dc2d..e32389a97030 100644 --- a/mm/khugepaged.c +++ b/mm/khugepaged.c @@ -103,6 +103,7 @@ static struct khugepaged_scan khugepaged_scan = { .mm_head = LIST_HEAD_INIT(khugepaged_scan.mm_head), }; +#ifdef CONFIG_SYSFS static ssize_t scan_sleep_millisecs_show(struct kobject *kobj, struct kobj_attribute *attr, char *buf) @@ -295,6 +296,7 @@ struct attribute_group khugepaged_attr_group = { .attrs = khugepaged_attr, .name = "khugepaged", }; +#endif /* CONFIG_SYSFS */ #define VM_NO_KHUGEPAGED (VM_SPECIAL | VM_HUGETLB) @@ -873,13 +875,13 @@ static bool __collapse_huge_page_swapin(struct mm_struct *mm, unsigned long address, pmd_t *pmd, int referenced) { - pte_t pteval; int swapped_in = 0, ret = 0; - struct fault_env fe = { + struct vm_fault vmf = { .vma = vma, .address = address, .flags = FAULT_FLAG_ALLOW_RETRY, .pmd = pmd, + .pgoff = linear_page_index(vma, address), }; /* we only decide to swapin, if there is enough young ptes */ @@ -887,19 +889,19 @@ static bool __collapse_huge_page_swapin(struct mm_struct *mm, trace_mm_collapse_huge_page_swapin(mm, swapped_in, referenced, 0); return false; } - fe.pte = pte_offset_map(pmd, address); - for (; fe.address < address + HPAGE_PMD_NR*PAGE_SIZE; - fe.pte++, fe.address += PAGE_SIZE) { - pteval = *fe.pte; - if (!is_swap_pte(pteval)) + vmf.pte = pte_offset_map(pmd, address); + for (; vmf.address < address + HPAGE_PMD_NR*PAGE_SIZE; + vmf.pte++, vmf.address += PAGE_SIZE) { + vmf.orig_pte = *vmf.pte; + if (!is_swap_pte(vmf.orig_pte)) continue; swapped_in++; - ret = do_swap_page(&fe, pteval); + ret = do_swap_page(&vmf); /* do_swap_page returns VM_FAULT_RETRY with released mmap_sem */ if (ret & VM_FAULT_RETRY) { down_read(&mm->mmap_sem); - if (hugepage_vma_revalidate(mm, address, &fe.vma)) { + if (hugepage_vma_revalidate(mm, address, &vmf.vma)) { /* vma is no longer available, don't continue to swapin */ trace_mm_collapse_huge_page_swapin(mm, swapped_in, referenced, 0); return false; @@ -913,10 +915,10 @@ static bool __collapse_huge_page_swapin(struct mm_struct *mm, return false; } /* pte is unmapped now, we need to map it */ - fe.pte = pte_offset_map(pmd, fe.address); + vmf.pte = pte_offset_map(pmd, vmf.address); } - fe.pte--; - pte_unmap(fe.pte); + vmf.pte--; + pte_unmap(vmf.pte); trace_mm_collapse_huge_page_swapin(mm, swapped_in, referenced, 1); return true; } @@ -1240,6 +1242,7 @@ static void retract_page_tables(struct address_space *mapping, pgoff_t pgoff) struct vm_area_struct *vma; unsigned long addr; pmd_t *pmd, _pmd; + bool deposited = false; i_mmap_lock_write(mapping); vma_interval_tree_foreach(vma, &mapping->i_mmap, pgoff, pgoff) { @@ -1264,10 +1267,26 @@ static void retract_page_tables(struct address_space *mapping, pgoff_t pgoff) spinlock_t *ptl = pmd_lock(vma->vm_mm, pmd); /* assume page table is clear */ _pmd = pmdp_collapse_flush(vma, addr, pmd); + /* + * now deposit the pgtable for arch that need it + * otherwise free it. + */ + if (arch_needs_pgtable_deposit()) { + /* + * The deposit should be visibile only after + * collapse is seen by others. + */ + smp_wmb(); + pgtable_trans_huge_deposit(vma->vm_mm, pmd, + pmd_pgtable(_pmd)); + deposited = true; + } spin_unlock(ptl); up_write(&vma->vm_mm->mmap_sem); - atomic_long_dec(&vma->vm_mm->nr_ptes); - pte_free(vma->vm_mm, pmd_pgtable(_pmd)); + if (!deposited) { + atomic_long_dec(&vma->vm_mm->nr_ptes); + pte_free(vma->vm_mm, pmd_pgtable(_pmd)); + } } } i_mmap_unlock_write(mapping); @@ -1401,6 +1420,9 @@ static void collapse_shmem(struct mm_struct *mm, spin_lock_irq(&mapping->tree_lock); + slot = radix_tree_lookup_slot(&mapping->page_tree, index); + VM_BUG_ON_PAGE(page != radix_tree_deref_slot_protected(slot, + &mapping->tree_lock), page); VM_BUG_ON_PAGE(page_mapped(page), page); /* @@ -1421,9 +1443,10 @@ static void collapse_shmem(struct mm_struct *mm, list_add_tail(&page->lru, &pagelist); /* Finally, replace with the new page. */ - radix_tree_replace_slot(slot, + radix_tree_replace_slot(&mapping->page_tree, slot, new_page + (index % HPAGE_PMD_NR)); + slot = radix_tree_iter_resume(slot, &iter); index++; continue; out_lru: @@ -1519,9 +1542,10 @@ tree_unlocked: if (!page || iter.index < page->index) { if (!nr_none) break; - /* Put holes back where they were */ - radix_tree_replace_slot(slot, NULL); nr_none--; + /* Put holes back where they were */ + radix_tree_delete(&mapping->page_tree, + iter.index); continue; } @@ -1530,7 +1554,9 @@ tree_unlocked: /* Unfreeze the page. */ list_del(&page->lru); page_ref_unfreeze(page, 2); - radix_tree_replace_slot(slot, page); + radix_tree_replace_slot(&mapping->page_tree, + slot, page); + slot = radix_tree_iter_resume(slot, &iter); spin_unlock_irq(&mapping->tree_lock); putback_lru_page(page); unlock_page(page); @@ -1614,8 +1640,8 @@ static void khugepaged_scan_shmem(struct mm_struct *mm, present++; if (need_resched()) { + slot = radix_tree_iter_resume(slot, &iter); cond_resched_rcu(); - slot = radix_tree_iter_next(&iter); } } rcu_read_unlock(); |